You hold a dagger in your hand and concentrate on it, evoking the power of the spell. A duplicate of the dagger, made of translucent force, appears beside it and flies off at your command.

You bring into being a tiny blade of force. The blade flies at a speed of 40 feet (perfect) and attacks any target within its range, as you desire, starting in the round when you cast the spell. The blade attacks on your turn once per round, striking with an attack bonus equal to your base attack bonus + your Intelligence bonus or your Charisma bonus (for wizards and sorcerers, respectively; if you are a cleric, the blade's attack bonus is equal to your base attack bonus + your Wisdom bonus) and deals 1d4 points of damage, with a critical threat range of 19-20. If an ally also attacks the creature, the blade moves on your turn to flank the target. As a force effect, it can strike ethereal and incorporeal creatures. The blade cannot be attacked.

Each round after the first, you can use a standard action to switch the blade to a new target; otherwise, it continues to attack the same target. If an attacked creature has spell resistance, the resistance is checked the first time the persistent blade strikes. If the blade is successfully resisted, the spell is dispelled. If not, the blade has its normal full effect on that creature for the duration of the spell.